Webster's Revised Unabridged Dictionary · 1913

Groundling

Groundling , noun

[Ground + -ling.]

1.
(Zoology) A fish that keeps at the bottom of the water, as the loach.
2.
A spectator in the pit of a theater, which formerly was on the ground, and without floor or benches.
No comic buffoon to make the groundlings laugh. — Coleridge